As is well known, in a process of manufacturing glass sheet products to be used for flat panel displays (FPD) such as a liquid crystal display, a plasma display, an electroluminescence display, and an organic light-emitting diode display, and for solar cells, a small-area glass sheet is cut out of a large-area glass sheet, and an edge portion extending along each side of the glass sheet is trimmed off.
A laser fusing method is publicly known as a method of cutting a glass sheet as described above. In Patent Literature 1, one example of the laser fusing method is disclosed. The laser fusing method involves cutting an object to be processed, which is as an object to be cut, by irradiating the object to be processed with a laser along a preset cutting line extending in a surface direction of the object to be processed and removing a portion molten through heating with the laser by, for example, jetting an assist gas.
When the laser fusing method is applied for cutting the glass sheet, a cutting end portion of each piece of the cut glass sheet is formed so as to have a smooth fire polished surface. As a result, the same effect as or a higher effect than that of polishing for a mirror-smooth surface, which is carried out by a mechanical method, can be exerted on the cutting end portion.